The present invention relates to a connecting mechanism of a light source device for an endoscope, to which a connector of the endoscope is connected.
A light source device for an endoscope generally has a socket as a connecting mechanism, and a connector mounted at the end of the cable of the endoscope is connected to the socket. When the connector is connected to the socket, an electrical system, an optical system and a gas and water feeding system of the endoscope are respectively connected to those of the light source device.
The connector of the endoscope has a light guide tube, a gas feeding tube and a plurality of contact pins, which are projected from the bottom surface of a recess portion formed at the end face of a connector body. In other words, at least the base ends of the light guide tube, the gas feeding tube and the contact pins are enclosed by an engaging column defining the recess portion.
As an endoscope cleaning technique has recently made progress, the entire endoscope has been formed in a waterproof structure for its disinfection and irrigation. Since the recess portion is formed at the end of the connector body, as described above, and since the light guide tube, the gas feeding tube and the contact pins are projected in the recess portion, detergent remains, even if the endoscope is taken out of a detergent tank, in the gaps between the tubes and between the pins in the bottom of the recess portion, and such detergent cannot be wiped off.
Another connector has been proposed in which the entire structure has been altered: the end of the connector body is formed in a flat surface, a light guide tube and a gas feeding tube are projected from the flat surface, and a plurality of contacts are protruded on the outer peripheral surface of the body. Since the connector of this type does not have a recess portion on the outer surface of the body, detergent adhered to the surface of the connector body can be naturally wiped off after an irrigation, and even if the detergent remains on the outer surface of the connector body, the detergent can be readily wiped off.
When an endoscope having a connector which has an entirely altered structure as described above is used, the structure of the socket of a light source device should also be changed to match the connector. However, the light source device is expensive, and accordingly, it is not economical for users to prepare a plurality of light source devices with different sockets for the altered connectors.
From the above described facts, a connection system has been proposed which is capable of being used for the light source device of any type of socket, and which has obtained interchangeability between the connectors of different types and the light source device by employing two types of adapters between the connector of the endoscope and the socket of the light source device. However, the recent endoscope tends to use a multiplex transmission sytem for transmitting a number of signals by utilizing less signal lines. There arises a matching problem when the same photoelectric source device is used for both the endoscope which employs the above-described transmission system and the endoscope of the conventional type. Thus, in the proposed endoscope, an adapter for a light source device side and an adapter for a connector side are prepared to allow the matching therebetween, an electric system is associated therewith, and the necessary electric processing is executed. In other words, two types of adapters are used to match the endoscopes of different types. When two such adapters are thus used, it is disadvantageous that the structure becomes complicated and expensive, and the handling also becomes complicated.
Further, in order to reproduce individual signals from a plurality of superposed signals, the signals are fed through the both adapters. Thus, the signals should twice pass through the contacts of a contacting type, thereby disadvantageously deteriorating the reliability.
Then, a connecting mechanism is proposed which is capable of simply connecting the connectors of different types of endoscopes, without using the adapters of other members, by providing a plurality of engaging stationary units for fixedly positioning the connectors to be connected corresponding to the different types of connectors in a socket.
However, the connecting mechanism of this type is constructed to connect a variety of connectors by utilizing the difference of the inner diameters between the engaging stationary units. Therefore, even if there is an engaging stationary unit adapted for a special connector, the special connector makes contact with another engaging stationary unit, not used at that time, with the result that the connector cannot be plugged in. In other words, when using the endoscope having this special connector, it has the drawback that the adapters should still be used.